title: Noninvasive procedure for in situ determination of skin surface aspartic proteinase activity in animals; implications for human skin.
abstract: The present study demonstrated a noninvasive procedure for in situ determination of stratum corneum aspartic proteinase in the living animal. A non-leaky well, containing [125I]S-carboxymethylated insulin B-chain (ICMI) as a substrate, was constructed on the shaved back of anesthetized guinea pigs and rats. The enzymatic activity was determined by measuring the radiolabeled trichloroacetic acid soluble material. We demonstrated pepstatin-sensitive proteinase activity bound to the skin surface indicating the involvement of aspartic proteinase(s) such as cathepsin D and/or E. Aged rats had about six fold lower activity than young animals. The proteinase activity was inhibited by the alkylating agent mechlorethamine and by the cosmetic propylene glycol. A similar procedure was carried out with intact human skin pieces obtained during plastic surgery. The activity was inhibited by antihuman cathepsin D antibodies. Cathepsin D was immunohistochemically localized in the corneal and granular layers of the epidermis. Skin surface aspartic proteinase/cathepsin D activity may serve as a marker for skin aging or for certain skin disorders leading to a new approach to their medical treatments.
authors.affiliation: Department of Pharmacology, School of Pharmacy, Faculty of Medicine, Hebrew University, Jerusalem, Israel. wormser@yam-suff.cc.huji.ac.il
authors.forename: U
authors.initials: U
authors.lastname: Wormser
authors.forename: R
authors.initials: R
authors.lastname: Kohen
authors.forename: E V
authors.initials: EV
authors.lastname: Moor
authors.forename: A
authors.initials: A
authors.lastname: Eldad
authors.forename: R
authors.initials: R
authors.lastname: Gal
authors.forename: A
authors.initials: A
authors.lastname: Nyska
authors.forename: B
authors.initials: B
authors.lastname: Brodsky
mesh_terms: D000375:Aging / Q000378:metabolism; D000477:Alkylating Agents / Q000494:pharmacology; D000818:Animals; D016282:Aspartic Acid Endopeptidases / Q000032:analysis* / Q000037:antagonists & inhibitors; D002402:Cathepsin D / Q000032:analysis* / Q000037:antagonists & inhibitors; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006168:Guinea Pigs; D006801:Humans; D007150:Immunohistochemistry; D007509:Irritants / Q000494:pharmacology; D008466:Mechlorethamine / Q000494:pharmacology; D019946:Propylene Glycol / Q000494:pharmacology; D051381:Rats; D012867:Skin / Q000187:drug effects / Q000201:enzymology*
chemical_list: D000477:Alkylating Agents; D004791:Enzyme Inhibitors; D007509:Irritants; D008466:Mechlorethamine; D019946:Propylene Glycol; D016282:Aspartic Acid Endopeptidases; D002402:Cathepsin D